The Short Answer: Yes, Offline
The campaign is a single-player experience stored entirely on the device. After installation and the complete game data download, the story, exploration, tombs and collectibles all function without any connection, indefinitely. Aeroplane mode is a legitimate way to play the whole game.
That places it in the honourable minority of big mobile releases that respect offline play. There are no energy timers, no server checks gating the campaign and no content locked behind a connection once the game is fully on your phone.
Fully offline after setup:
- The whole story campaign
- Exploration and Challenge Tombs
- Camps, skills and upgrades
- All collectibles and saves



